AUSTIN, Texas (CNN, KVUE) - 66 people in the U.S. have died from West Nile virus infections this year, and nearly 1,600 Americans have become sickened by it, putting 2012 on track to be the worst year for contracting the virus.

Cases of West Nile continue to grow across the U.S. 48 states have reported cases of the virus this year. 45 percent of those cases are in Texas.

"I think one of the things that we look at this past year, we had a very mild winter, so no freeze that really killed off the mosquitoes," says Dr. Philip Huang, with Travis County Medical.

Dr. Huang says while Dallas County has seen the worst of the virus, central Texas has its fair share of infected mosquitoes.

"West Nile virus is in Travis County. It's in our community," he says.

40 human cases have been reported in Travis County, six in Williamson, and four in Hays. Two central Texans have died from the virus.